Targeting of Arabidopsis KNL2 to Centromeres Depends on the Conserved CENPC-k Motif in Its C Terminus.

KINETOCHORE NULL2 (KNL2) is involved in recognition of centromeres and in centromeric localization of the centromere-specific histone cenH3. Our study revealed a cenH3 nucleosome binding CENPC-k motif at the C terminus of Arabidopsis thaliana KNL2, which is conserved among a wide spectrum of eukaryotes. Centromeric localization of KNL2 is abolished by deletion of the CENPC-k motif and by mutating single conserved amino acids, but can be restored by insertion of the corresponding motif of Arabidopsis CENP-C. We showed by electrophoretic mobility shift assay that the C terminus of KNL2 binds DNA sequence-independently and interacts with the centromeric transcripts in vitro. Chromatin immunoprecipitation with anti-KNL2 antibodies indicated that in vivo KNL2 is preferentially associated with the centromeric repeat pAL1 Complete deletion of the CENPC-k motif did not influence its ability to interact with DNA in vitro. Therefore, we suggest that KNL2 recognizes centromeric nucleosomes, similar to CENP-C, via the CENPC-k motif and binds adjoining DNA.

Sandmann M ，Talbert P ，Demidov D ，Kuhlmann M ，Rutten T ，Conrad U ，Lermontova I ... -  《-》

Depletion of KNL2 Results in Altered Expression of Genes Involved in Regulation of the Cell Cycle, Transcription, and Development in Arabidopsis.

Boudichevskaia A ，Houben A ，Fiebig A ，Prochazkova K ，Pecinka A ，Lermontova I ... -  《INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES》

Arabidopsis kinetochore null2 is an upstream component for centromeric histone H3 variant cenH3 deposition at centromeres.

Lermontova I ，Kuhlmann M ，Friedel S ，Rutten T ，Heckmann S ，Sandmann M ，Demidov D ，Schubert V ，Schubert I ... -  《-》

Association of M18BP1/KNL2 with CENP-A Nucleosome Is Essential for Centromere Formation in Non-mammalian Vertebrates.

Centromeres are specified and maintained by sequence-independent epigenetic mechanisms through the incorporation of CENP-A into centromeres. Given that CENP-A incorporation requires the Mis18 complex to be in the centromere region, it is necessary to precisely understand how the Mis18 complex localizes to the centromere region. Here, we showed that centromere localization of the Mis18 complex depends on CENP-A, but not CENP-C or CENP-T, in chicken DT40 cells. Furthermore, we demonstrated that M18BP1/KNL2, a member of the Mis18 complex, contained the CENP-C-like motif in chicken and other vertebrates, which is essential for centromere localization and M18BP1/KNL2 function in DT40 cells. We also showed that in vitro reconstituted CENP-A nucleosome, but not H3 nucleosome, bound to the CENP-C-like motif containing M18BP1/KNL2. Based on these results, we conclude that M18BP1/KNL2 is essential for centromere formation through direct binding to CENP-A nucleosome in non-mammalian vertebrates. This explains how new CENP-A recognizes the centromere position.

Hori T ，Shang WH ，Hara M ，Ariyoshi M ，Arimura Y ，Fujita R ，Kurumizaka H ，Fukagawa T ... -  《-》

Scm3 is a centromeric nucleosome assembly factor.

Shivaraju M ，Camahort R ，Mattingly M ，Gerton JL ... -  《-》